Allow multiple recipes to be selected

[keckrich]

Having the ability to select multiple products would be very useful. For example, selecting blue, red, and yellow matrix cubes, and then it would show the combined steps

[Martin-Pitt]

I'll have to rethink this since this was designed to be a single-recipe-only calculator from the get go to be honest.

This would synergise very well with #10, once you can show those combined steps in different visual ways.

[keckrich]

I'll have to rethink this since this was designed to be a single-recipe-only calculator from the get go to be honest.

This would synergise very well with #10, once you can show those combined steps in different visual ways.

My initial thought after a quick peak at the code would be to make an anonymous/ephemeral recipe that requires all the different products you want to calculate. But that approach probably has its own issues.